This invention relates to mounting and/or traversing devices, and more specifically to a mounting and traversing device which is particularly suited for employment with an in situ particle size measuring device.
One of the important parameters in many industrial processes is particle size. As such, it has long been known in the prior art to provide devices that are capable of being employed for purposes of effecting measurements of particles. To this end, the prior art is replete with examples of various types of devices that have been used to obtain measurements of particles. In this regard, in many instances discernible differences exist in the technique by which the measurement of the particles is accomplished. The existence of such differences is, in turn, attributable for the most part to the diverse functional requirements that are associated with the specific application in which such devices are designed to be employed. For instance, in the selection of the particular type of device that is to be utilized for a specific application one of the principal factors to which consideration must be given is that of the nature of the substance of which the particle that is to be measured is formed. Another factor to which consideration must be given is that of the nature of the substance in which the particles are present at the time they are being measured. Yet another factor to which consideration must be given is the relative size of the particles that are to be measured.
Some of the techniques that have been utilized heretodate by the prior art for purposes of accomplishing the measurement of particles include acoustical techniques, optical counting techniques, electrical counting techniques, sedimentation techniques, separation techniques and surface measurement techniques. Moreover, the kinds of particles with which such techniques have been sought to be applied for purposes of making measurements of the particles include such particles as blood particles, food particles, chemical particles, mineral particles as well as others. In addition, diverse ones of the techniques to which reference has been had hereinbefore have been sought to be employed for purposes of accomplishing the measurement of particles while the latter are present in a variety of different types of fluid substances such as various types of gases and various types of liquids.
Unfortunately, however, the devices that have been available in the prior art heretofore for purposes of enabling the techniques to be carried out which have been referred to above have been found to be disadvantageously characterized in one or more respects. To this end, where such devices have been sought to be employed in connection with applications involving industrial processes for purposes of generating information relating to particle size that could be utilized to accomplish, as needed, adjustments to the industrial process, it has not been possible through the use of prior art forms of devices to generate the information required in a sufficiently fashion and/or with the desired degree of accuracy. Namely, it has proven to take far too long and/or to require far too much effort to generate the desired information pertaining to particle size for this information to be of any significant value insofar as concerns the utilization thereof for purposes of making timely adjustments to the industrial process. In large measure this is based on the fact that with the prior art devices that have heretofore been available for use for purposes of effectuating particle size measurements it has not been possible to make measurements in situ therewith. As a result, in order to make use of the prior art devices that have been available heretofore there has most often existed a need to collect a sample from the medium in which are present the particles that it is desired to measure, a need to transport this sample to the device that is to be used to accomplish the particle size measurements, a need to actually perform the particle size measurements with the device, and then finally based on the results of the particle size measurements effectuate whatever adjustments must be made to the industrial process in order to ensure that the particles do in fact embody the size that they must have if the particular industrial process from which the particles that were measured were taken is to be successfully operated.
By way of exemplification and not limitation, one form of industrial process in which particle size is known to be an important consideration for the successful operation of the process is the combustion of pulverized coal. As regards the combustion of pulverized coal, it has long been known that an essential component of any steam generation system that utilizes pulverized coal as a fuel is the apparatus in which the coal is pulverized in order to render the coal suitable for such usage. One form of apparatus in particular that has frequently been used for purposes of accomplishing the pulverization of coal, although various types of apparatus have been known to have been employed for this purpose, is that which those in the industry commonly refer to as a bowl mill. The bowl mill obtains its name principally from the fact that the pulverization, i.e., grinding, of the coal that takes place therewithin occurs on a grinding surface which in configuration bears a resemblance somewhat to that of a bowl. By way of illustration, reference may be had to U.S. Pat. No. 3,456,971, which issued Sept. 9, 1969 to J. F. Dalenberg et al and which is assigned to the same assignee as the present invention, for a showing of a prior art form of bowl mill. This patent contains a teaching of both the nature of the construction and the mode of operation of a bowl mill that is suitable for use for purposes of effectuating the pulverization of the coal that is used to fuel a coal-fired steam generator.
The efficient combustion of pulverized coal, particularly as it relates to the use of pulverized coal as a fuel in a steam generation system, requires that the coal particle size be held close to a specified particle size distribution. Typically, for a medium reactivity coal this is 70% passing through 200 mesh, and 1% not passing through 50 mesh. Based on an economic evaluation for a typical 500 MW coal-fired steam generator power plant, it has been determined that through an increase in carbon conversion rate which in turn is achievable by maintaining a specified particle size distribution, it is possible to realize significant savings amounting to hundreds of thousands of dollars on an annualized basis in the cost of operating a power plant of the size to which reference has been made hereinbefore. Obviously, however, the savings that will be actually realized insofar as any specific power plant that is fueled with pulverized coal is concerned by virtue of maintaining the coal particle size close to a specified particle size distribution will be dependent on a number of factors including the reaction kinetics of the coal, i.e., how sensitive the combustion efficiency is to particle size for the specific coal being used, and how well and often control is exercised over the bowl mill to maintain the optimum size distribution of the coal particles. In every instance, however, maintaining the size distribution of the coal particles close to the optimum should result in some measure of fuel savings.
Other benefits should also flow from the fact that better control is being exercised over the size distribution of the coal particles. In this regard, reference is had to the fact that there should be reduced slagging in the steam generator due to better control over the size distribution of the coal particles. In addition, it may be possible in some instances to make use of the fact that deviations are occurring in the size distribution of the coal particles from that which should be present as a maintenance and diagnostic aid to detect problems associated with the operation of the bowl mill in which the pulverization of the particles of coal that have been measured was effected. Also, the possibility exists for exercising continuous control over the operation of the bowl mill through the use of the information garnered from having made coal particle size measurements. Yet another possibility is to utilize the information acquired from the performance of coal particle size distribution measurements for purposes of obtaining an indication of the fuel-to-air ratio in the coal feed pipe by means of which, as is well-known to all, the pulverized coal particles are conveyed from the bowl mill to the steam generator wherein the combustion of the pulverized coal particles takes place.
Thus, there has been evidenced in the prior art a need for a new and improved form of mounting device suitable for use for purposes of effecting the mounting of a particle size measuring device such that measurements relating to particle size can be made in situ therewith. Moreover, a need has thus been evidenced in the prior art for a new and improved form of traversing device which would be suitable for use for purposes of enabling a particle size measuring device to be traversed across a flow stream in which particles are present so that measurements can be obtained of these particles as the particle size measuring device is being traversed across the flow stream. Further, a need has been evidenced in the prior art for a new and improved form of mounting and traversing device which is capable of being subjected to rugged handling without being adversely affected thereby. In addition, a need has been evidenced fOr a new and improved form of mounting and traversing device which is characterized by the fact that when employed with a particle size measuring device the mounting and traversing device is operative to maintain the proper alignment of the particle size measuring device while the latter is being employed for purposes of making particle size measurements. Also a need has been evidenced for a new and improved form of mounting and traversing device which is characterized by the fact that the device is capable of being installed easily and rapidly.
It is, therefore, an object of the present invention to provide a new and improved mounting and traversing assembly suitable for use with devices wherein in connection with the operation thereof the devices are required to be mounted and traversed.
It is another object of the present invention to provide such a mounting and traversing assembly which is particularly suited for employment with particle size measuring devices wherein it is desired through the use of the particle size measuring devices to obtain therewith measurements in situ of particle size.
It is still another object of the present invention to provide such a mounting and traversing assembly which is suited for employment for purposes of effecting the mounting and traversing of a particle size measuring device particularly in applications in which concern over the wear occasioned by the positioning of the particle size measuring device in the flow stream of the fluid medium containing the particles to be measured, if the particle size measuring device were to be permanently positioned therein, is a consideration.
A further object of the present invention is to provide such a mounting and traversing assembly which is suited for employment for purposes of effecting the mounting and traversing of a particle size measuring device particularly in applications in which because the width of the flow stream of the fluid medium in which the particles are entrained is sufficiently large as to render it desirable to make measurements with the particle size measuring device of particles at various locations within the aforereferenced flow stream.
A still further object of the present invention is to provide such a mounting and traversing assembly which is particularly suited for employment with a particle size measuring device and which is characterized by the fact that the mounting and traversing assembly is capable of being subjected to rugged handling without being adversely affected thereby.
Yet another object of the present invention is to provide such a mounting and traversing assembly which is particularly suited to be employed with a particle size measuring device and which is characterized by the fact that when employed with a particle size measuring device such a mounting and traversing assembly is operative to maintain the proper alignment of the particle size measuring device while the latter is being employed for purposes of making particle size measurements.
Yet still another object of the present invention is to provide such a mounting and traversing assembly which is particularly suited to be employed with a particle size measuring device, and when being so employed is characterized by the fact that the mounting and traversing assembly is capable of being installed easily and rapidly, while yet being relatively inexpensive to provide.